'Nobody has given up': Family shocked by cold case arrest

VIVID memories of a young man who was easily led astray came flooding back to Robert Grayson's family this week, almost 25 years after he disappeared.

A relative of Mr Grayson's said the family was shocked and relieved when they learned Russell Williams had been charged with his murder.

Police allege Mr Williams murdered Mr Grayson and Derek Van Der Poel, who were last seen in May 1993 when they were tending to a marijuana crop at Kroombit Tops.

A family member, who did not want to be named, told The Observer Mr Grayson was not a bad person.

"It's surprising that no matter how many years go past, something like this just brings back all those vivid memories," they said.

"He wasn't a bad kid, he was just very naive and easily led."

Referring to Mr Grayson as "Bob", they said his late grandmother Jean Fischer, of Warwick, would have been very proud to hear the police had made a major breakthrough in the cold case.

Mrs Fischer, known by her grandchildren as "Mama", reported Mr Roberts as missing on August 8, 1994 to the Calliope Police Station.

"We often went a long time between hearing from Bob," the relative said.

Russell Williams being led by police at the Gladstone station after he was charged with two counts of murder and drug production.Queensland Police

"Every now and again you would get a call from Bob saying I'm working here, or I'm not doing much, he'd just contact you out of the blue. But it was 12 months and (Jean) said it's been too long, she said he would've contacted us...hopefully now we might be on the road to get some sort of closure."

The news of Mr Williams' arrest this week came as a surprise to the family.

It also made them proud that more than 20 years of dedicated investigation by the Gladstone Police and Homicide Squad in Brisbane had resulted in the major development.

The family member said from the day Mrs Fischer reported Mr Grayson missing, to then Calliope Police officer-in-charge Darryl Saw, the investigation had been thorough.

"(Darryl Saw) did everything in his power to find out everything he possibly could," they said.

"This whole time nobody has given up and we do really appreciate that."